<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title></title>
 <script src="https://unpkg.com/vue/dist/vue.js"></script>
</head>
<body>
<div id="demo">{{ fullName }}</div>
</div>

<script>
var vm = new Vue({
  el: '#demo',
  data: {
    firstName: 'Foo',
    lastName: 'Bar'
  },
  computed: {
    fullName: function () {
      return this.firstName + ' ' + this.lastName
    }
  }
})
</script>	
</body>
</html></body>
</html>
